On the occasion of 150th birth anniversary of Mahatma Gandhi artist from 124 countries collaborate to recreate to sing his favorite Bhajan “Vaishnav Jan to tene re Kahiye je..”

Bhajan means a simple poetic words who shows a deep message of the life in simple words. This Bhajan was written by Lord Krishna’s devotee Narsinh Mehta, who is considered as first notable poet of Gujarati Language.

Videos from different regions of the world have also been put together in a fusion video of about five minutes to give flavour to the bhajan. Amongst the star performers is President of Nauru Baron Divavesi Waqa. Waqa’s gesture was not just a tribute to Gandhi but was also a personal gift from him to Prime Minister Modi.

I am sharing the meaning of lyrics below. It is a beautiful song with profound meaning. Vaishnav is lover of God…..and a true lover of God has to have the following mentioned qualities.

Before Copernicus and Heliocentricity, the ancient Greeks believed that the sun and the planets moved around the Earth in giant circles. But upon closer observation, they could see that was not always the case. Sometimes, the planets appeared to move backwards in the sky. So Greco-Roman mathematician, astronomer, geographer, and all round G, Ptolemy (pictured above looking knowledgeable), came up with a clever solution. He theorized that the planets must then not only go around the earth in big circles, but also in an additional little circle, called an epicycle, at the same time.

Pretty soon, observational data disproved them once again. So they just added some more circles. And some more. They kept adding circles until the resultant map of our solar system looked like a kaleidoscope.

The Ptolemaic model looked good. So good, that it stuck around for 1,300 years unchallenged. But it turned out to be wildly incorrect, and not just because we now know that the Earth and planets move around the sun. The problem with the epicycle theory is that it contains no information about the actual orbits themselves. Yes – for many years the model could provide accurate predictions, but that is only by nature of the relationship of the circles. By adding up enough circles, you can approximate any orbit to some degree of accuracy. In fact you can make any signal – a radio signal, a piece of music, data from your computer etc. – from just adding up enough circular paths. How is this possible? Well Euler allows us to represent these circular paths using complex numbers.

So each point moving in a plane can be thought of as a complex function of time. If you take a planet, or whatever, moving on a circle with the radius R and the angular frequency ω, then the equation describing the position of our planet as a function of time would be:

z(t)=Reiωt

Let’s say you’re moving around two epicyclic circles now, the equation would become:

z(t)=R1eiω1t+R2eiω2t

Now picture adding infinite many circles together. We end up with the equation:

z(t)=∫∞−∞R(ω)eiωtdω

The function R(ω) is the Fourier Transform of z(t)! And not just for planets, if you have any time-dependent path or signal, it can be replicated exactly by infinitely many circles of varying frequencies added together. And the radii of these circles is the fourier transform of the path.

Let’s look closer at the idea of representing a signal as circular or sinusoidal waves. Check out a square wave (in 1D), for example.

If I wanted a square wave, but only had a source that produced sine waves, could I do that?

In the image below, both columns begin with the same sine wave. The left column contains harmonics of the sine wave. In the right column, you can see the effect of adding those harmonics to the sequence. Surprise! Our squiggly sine waves are combining to look more and more like a square wave.

This concept is the basis of the Fourier Series, which shows that you can represent a periodic function as a discrete sum of complex exponentials…. or in digestible terms, as a bunch of circular functions, not continuous, added together (see above).

The Fourier Transform also breaks stuff apart into its simple trigonometric components… however, it deals with messier, nonperiodic signals, which can’t reduce to a clean sum of discrete sine waves. Instead, the FT represents nonperiodic signals as a continuous superposition or integral of complex exponentials. Both the FT and FS are part of Fourier Analysis, which looks at how general functions can be approximated by sums of simpler trigonometric functions.

When we apply the FT, our data hasn’t changed. Were just looking at it from a different domain.

The most common example of this is looking at data in the frequency domain. If you were to put all those waves in the frequency domain back together, you would get the original signal.

So why go through all this trouble and do this at all? One advantage of being able to switch between multiple domains, is that linear operations in one domain have a corresponding operation in the other. For example, differentiation in the time domain corresponds to multiplication by the frequency for most values… making differential equations easier to work through in the frequency domain. There are endless uses, applications, and representations of the FT, making it a crucial tool in signal analysis, image processing, optics, etc.

A teenager in an African high school asked a physics lecturer “Why is it that when I put hot water and cold water in the freezer together, the hot liquid freezes first?”

His classmates laughed at him; even his teacher laughed at him; but the physics lecturer, intrigued, decided to try it out; and sure enough, the kid was right. The two of them studied the problem and published their results; the phenomenon is now known as the Mpemba effect, named after the young student, Erasto Mpemba.

There’s a link to the original paper here – it’s well worth a read, both for Mpemba’s laconic narrative and Dr Osborne’s lucid open-mindedness. “No question should be ridiculed ….. for everyday events are seldom as simple as they seem, and it is dangerous to pass a superficial judgment on what can and cannot be.”

Sometimes It’s hard to stay awake till 12am to wish your loved one’s and close friendsand end up sleeping.

So I’ve written a script to solve this problem and let my script does rest of work on behalf of me.

This is how it looks after completion , this work is automated by my script( watsapp pic below).

You can write script to remember future birthdays and wishing them aswell and schedule them.

Let’s start with code

Pre-requisite

First you must install these:-

1) Python Bindings for Selenium ( Browser Automation software )

pip install selenium

2) Chrome webdriver
Download Chrome driver from here: Chromedriver download page( choose your specific version )
Extract it in a known location , as we need the location later

3) Chromium Web Browser( Open source version of chrome browser )

sudo apt–get install chromium–browser

That’s it! You are all set.

Lets dive in right away-

fromselenium importwebdriver

fromselenium.webdriver.support.ui importWebDriverWait

fromselenium.webdriver.support importexpected_conditions as EC

fromselenium.webdriver.common.keys importKeys

fromselenium.webdriver.common.byimportBy

importtime

# Replace below path with the absolute path

# to chromedriver in your computer

driver =webdriver.Chrome('/home/ads/Downloads/chromedriver')

driver.get("https://web.whatsapp.com/")

wait =WebDriverWait(driver,600)

# Replace 'Friend's Name' with the name of your friend

# or the name of a group

target ='"Friend\'s Name"'

# Replace the below string with your own message

string=" happy birthday boi"

x_arg ='//span[contains(@title,'+target +')]'

group_title =wait.until(EC.presence_of_element_located((

By.XPATH, x_arg)))

group_title.click()

inp_xpath ='//div[@class="input"][@dir="auto"][@data-tab="1"]'

input_box =wait.until(EC.presence_of_element_located((

By.XPATH, inp_xpath)))

fori inrange(100):

input_box.send_keys(string+Keys.ENTER)

time.sleep(1)

Keep your mobile phone with you. Choose whatsapp web from the top bar in whatsapp(3 dots)

Then Run the script ( make sure that you have added the absolute path for chromedriver and have replaced target variable with your friends name ). Scan the QR code that appears on the screen and enjoy.

You can make it responsive as well like kik bots just let your script read the input message of recipient and write command for further response… but it will be little lengthy.

Pro tip: You may get blocked by watsappif you make it responsive like bots …. Be safe!!!

Recently, Prof Vijay Savani, Mr. Praful Joshi and Mr. Aanand Christian from Nirma University, Ahmedabad came to my house for a formal meet and suddenly there was a question popped in discussion. Also, during my carrier working as Robotics and Automation engineer, I am always frequently exposed to this question that what is better PLC or Raspberri Pi? This question makes me think about the similarities as there are a few.

A PLC or Programmable Logic Controller is a very complicated piece of hardware which is designed to be robust and follows very specific design guidelines. PLCs usually have special parts like an IO board that is capable of digital and analog input and output control. The driving circuitry is inbuilt along with surge protection and reverse polarity protection. They usually have FPGAs installed to help the processor handle real time tasks extremely efficiently. They also designed to handle high and low temperatures and are designed to work at maximum capacity with no forced air cooling most of the time. They can also handle vibrations and have a long life cycle of 10 to 20 years, sometimes even more. Apart from that they can be programmed in many languages like Ladder logic, Instruction list, Structured text, C, Cpp etc. (IEC 61131–3).

Raspberry PI and Arduino boards are the most famous devices for rapid electronic prototyping and DIY home applications. However, their capabilities and flexibility are still largely under estimated in the industrial environment.

Raspberry PI and Arduino flexible programming, customizable signal types and easy adaptation to the existing installations can offer many benefits to the industrial world.

For instance, they could be great low cost and flexible alternatives to the usual industrial devices for adding remote control and monitoring functionality to small legacy industrial systems.

The 3 most common concerns about the use of such development boards in the industrial environment are:

Robustness in industrial environments

Safety

Industrial standard communication protocols

Robustness in industrial environments

There are already several ruggedized versions of Arduino and Raspberry available in the markets.

Multisensory Retail management system for audio, video, lighting and fragrances synchronization developed by TairolRadio for the San Siro football stadium in Milan (A.C. Milan and Internationale football clubs)

Safety

This is probably the most controvert and discussed topic in Internet: Are Raspberry and Arduino boards, and related based hardware, safe solutions for the industrial applications? There is not a simple answer, it depends by many factors and require for sure a change in the mind-set of the engineers.

The safety of an industrial application does not only depend by the PLC; It always matter of the integrity of the full project, how the systems and software are implemented and how the safety have been considered when designing the project.

This is where the flexibility of Arduino and Raspberry PI comes over. Modbus foundation has developed specific libraries to allow the two boards to communicate via their protocol.

Modbus is a serial communications protocol developed by Modicon (acquired by Schneider Electric) for its programmable logic controllers (PLCs); it has become the most common and adopted by many automation manufacturers such as Omron, Opto 22, Schneider and Mitsubishi.

The main reasons for the wide adoptions of Modbus in the industrial environment are:

developed for industrial use

royalty-free and open published

easy to use, install and maintain

few restrictions on vendors

Modbus allows many different devices, connected to the same network, to communicate together regardless the OEMs. The needs of putting in communication different devices from different manufacturers has become even highly important with the arrival of 4th industrial revolution; The Industry 4.0 and the Industrial IoT have given a second childhood to Modbus.

The following articles show how to remotely control HVAC systems by using Arduino based hardware and SCADA.

SCADA (Supervisory Control And Data Acquisition) is another industrial system for remote monitoring and control that operates with coded signals over communication channels (using typically one communication channel per remote station). The SCADA library for Arduino are openly published as well.

Arduino and Raspberry PI, in their ruggedized version, can be valuable and reliable alternatives to the well-established industrial devices (especially to connect to the internet of things small legacy industrial systems) pending an ad-hoc design of project to ensure safety.

This is an example of obfuscated code, or, in simpler terms, a mess of characters that are virtually impossible for humans to understand!

Essentially, this string is an encoding for a map of India. The characters used alternate, with one character telling the programme how many times to place a space, and the next telling it how many exclamation marks are needed.

I don’t want to get too technical, but the mess of characters corresponds to ASCII numbers, or just numbers, if you prefer, and each number gives the programme an instruction, for example to start a new line, or print an exclamation mark.

You can also get less obfuscated versions of this code for various languages, but this code is much longer, and a lot more complicated.

The applications of the Fourier transform is enormous, be it any field of science or engineering. However, I would like to pick two applications that I found very appealing, one in the field of Quantum Computing in breaking the RSA encryption and another in Radio Astronomical imaging.

RSA encryption is used in the internet for secure data transmission. The RSA encryption is highly secure due to the fact that the factorization of very large number is computationally hard for a classical computer. However, Peter Shor, who is a Professor at MIT Applied Mathematics, showed in 1994, that the factorization problem can be solved in polynomial time (please refer to P (complexity) – Wikipedia to know more about, polynomial time complexity) by a quantum computer, thereby effectively decrypting the RSA. Henceforth, the algorithm devised by him is known as Shor’s algorithm. The main catch of Shor’s algorithm is the conversion of factorization problem into a period finding problem, by invoking a property that was discovered by Euler. There are several intricacies in the algorithm which you can find in the link Shor’s Algorithm – Breaking RSA Encryption. Now, the period finding is the bottleneck for classical computers, which is speeded up by the Quantum Computers, by using what is known as the Quantum Fourier Transform (QFT – Quantum Fourier transform – Wikipedia). Here, the concept of Fourier transform and its fast implementation version FFT shows its ‘mightiness’.

Now, coming to Astronomy, the theorem known as Van Cittert-Zernike theorem (Van Cittert–Zernike theorem – Wikipedia) is used in astronomical imaging. According to this theorem, under certain conditions the Fourier transform of the mutual coherence function of a distant, incoherent source is equal to its complex visibility. Now, the terminology here might not give a direct insight of what is going on, but, all that we need to know is mutual coherence function represents the intensity or brightness of the source under observation, and visibility is the observable, that which we can directly get from a telescope. Conversion of these observables to an intensity distribution or an image is what Fourier transform does. All this comes under Interferometry and Aperture Synthesis in Radio Astronomy, which is a separate area of study by itself.